Chris Edwards

Hey all, normally I would never add weight to the car that wasn't necessary, but I decided to replace the battery in preparation for a slightly higher SCR motor I am putting together in the coming months. I've heard a few 11.25:1 motors at startup and the starters sound like they turn a bit slow. Also, the O'Reilly brand "Super Start" 75 series battery that was in the car (date marked 2012) seemed quite weak. If I left the radio on for 20 mins, the car barely wanted to start. The original battery can be seen here:

http://www.oreillyauto.com/site/c/de...0423&ppt=C0005

So I replaced the OE size Z06 battery (75 series) with the larger 78 series battery found in all 97-99 C5's, this is the one I chose:

http://www.oreillyauto.com/site/c/de...0423&ppt=C0005

The old 75 series had a CCA of 650amps while the new 78 series has a CCA of 850amps! Car starts much quicker now, but I weighed the new battery and it's 39 lbs while the old battery was only 30lbs. This has me quite distraught, as I have corner scaled the car and I'm concerned about adding 9lbs at a pretty high point in the car.

Any advice?

The other battery I'm considering is the 78 series Super Start Premium with a CCA of 700amps, which only weighs 24lbs!

http://www.oreillyauto.com/site/c/de...0423&ppt=C0005

froggy47

The last one is only a 2 yr warranty though. Not a good sign. The case size is different on all those, make sure you can fit & solidly bolt down whichever one you get.

mesospeedy

Do those have the vents like the stock battery? Since it's located inside the car, make sure whatever you use can be vented like the oe battery.